This invention relates to exercise equipment and more particularly to exercise equipment which automatically provides a changing workload.
It is known that, for maximum benefit, an athlete in training must push himself to his maximum strength limits. This is difficult to achieve with conventional weight training equipment such as a bench press machine or other general purpose or special purpose machines since generally the athlete has heretofore stopped exercising when he reaches his first point of momentary muscular failure (MMF). At that point, the athlete must either personally change the weight on the machine he is using, or a second person must change the weight for him so that the athlete can continue using the machine. This either unnecessarily interrupts the exercise, or requires the continual presence of a second, non-exercising partner. If the athlete were able to experience multiple MMF's during any one set of a specific exercise, he would eventually reach his absolute fatigue point (AFP). However, with conventional exercise equipment, the AFP is extremely difficult or impossible to reach due to the drawbacks described above.
Consider the case of an athlete lifting 120 pounds while doing bench presses. In this exercise, direct resistance is placed upon pectoral major and anterior deltoids. Soon, for example after only ten complete repetitions, this athlete is no longer able to complete another repetition. As a direct result, he stops exercising, even though he would be able to continue exercising at a lower weight amount, and ultimately reach his AFP. (AFP is the point in which no movement can occur even where the weight amount is as little as 10 per cent of what the athlete began with). At this point the athlete has reached only one MMF point. It is known that a muscle will recover up to 50 per cent of its strength in three seconds. This means that if the athlete was bench pressing 120 pounds ten times, after three seconds of rest he should be able to do up to six more repetitions, thus reaching multiple MMF's which is critical to hypertrophy. As is known, the central key to working out and obtaining results, is to push the muscle beyond its normal everyday demands.
U.S. Pat. No. 4,610,449 to Diercks addresses the particular problem of changing the weights on a conventional exercise machine, but the apparatus shown in Diercks could be improved. In Diercks there is only one solenoid which changes the weight resistance only a single time. Thus, although Diercks is an improvement over conventional exercise equipment in that it allows the user to experience two different weight resistances, it is not capable of providing more than two such resistances for a given use. Moreover, in Diercks the weight is changed at a predetermined time after the exercise starts.
Diercks could be improved since multiple changes of weight is an absolute necessity for reaching absolute muscular failure fatigue. It takes more than one momentary muscular failure point to reach absolute failure point (AFP). Moreover, in exercising the weight must be changed quickly and when the athlete needs the weight to change, not when a predetermined amount of time dictates that the weight is to be changed. A change in the weight should be due to need, namely when the athlete has reached an MMF point, not when a predetermined time expires. Although Diercks could be manually reset after the second MMF point is reached to provide third and fourth MMF's, the time taken in changing the position of the Diercks' apparatus, as described above, allows the muscles to recover sufficiently so that a MMF may not be readily reached at the new weight. Thus, it is very important that the weight be changed quickly.